Fuel distribution device

Abstract

Provided is a fuel distribution device 1 including a fuel distribution pipe 3, a fuel pipe 4, and a connecting member 5. The fuel distribution pipe 3 has a seat section 21 having a first convex curved surface 24 formed on an outer circumferential surface thereof. The fuel pipe 4 has a seal section 27 having a second concave curved surface 28 formed on an inner circumferential surface thereof, and a second convex curved surface 29 corresponding to the second concave curved surface 28 is formed on an outer circumferential surface thereof. The connecting member 5 presses the seal section 27 against the seat section 21 from an opposite side of the fuel distribution pipe 3. A radius of curvature SR2 of the second concave curved surface 28 is greater than a radius of curvature SR1 of the first convex curved surface 24.

The invention claimed is: 
     
       1. A fuel distribution device comprising:
 a fuel distribution pipe which distributes and supplies fuel to a plurality of fuel injection devices; 
 a fuel pipe connected to the fuel distribution pipe; and 
 a connecting member which connects the fuel distribution pipe and the fuel pipe, 
 wherein the fuel distribution pipe has a seat section having a first convex curved surface formed on an outer circumferential surface thereof so as to be reduced in diameter in a convex curved surface shape toward a tip on the fuel pipe side, 
 the fuel pipe has a seal section in which a second concave curved surface, which is enlarged in diameter in a concave curved surface shape toward the tip on the fuel distribution pipe side and against which the first convex curved surface abuts, is formed on an inner circumferential surface thereof, and a second convex curved surface corresponding to the second concave curved surface is formed on an outer circumferential surface, 
 the connecting member presses the seal section against the seat section from an opposite side of the fuel distribution pipe, 
 a radius of curvature of the second concave curved surface is greater than a radius of curvature of the first convex curved surface, 
 the first convex curved surface is formed in a spherical shape, 
 the second concave curved surface is formed in an aspherical shape, 
 a straight line, which connects a point on the second concave curved surface and a center of curvature of the second concave curved surface at the point, passes through a center of curvature of the first convex curved surface, and 
 a position of the center of curvature of the second concave curved surface changes depending on a position of the point on the second concave curved surface, and
 wherein the connecting member has
 a locking inner circumferential surface locked to the second convex curved surface from an opposite side of the fuel distribution pipe, and a screwing section screwed to an outer circumferential surface of the fuel distribution pipe to move the connecting member toward the fuel distribution pipe, and 
 the locking inner circumferential surface is formed in a conical shape, the conical shape having a linear cross-section passing through the central axis of the connecting member. 
 
 
 
     
     
       2. The fuel distribution device according to  claim 1 , wherein the radius of curvature of the second concave curved surface is set to be more than or equal to 1.01 times of the radius of curvature of the first convex curved surface; and
 wherein the radius of curvature of the second concave curved surface is set to be less than or equal to 2.00 times of the radius of curvature of the first convex curved surface.